The invention relates to a telescopic cover for protection of machine tools and other industrial equipment.
A telescopic cover is known, for example, from German Patent Specification No. 33 30 289. In that disclosure the support rollers are each arranged so as to be capable of limited swinging movement like a pendulum in an angular range of approximately 5.degree. about a horizontal axis which extends in the direction of travel. The intention is that, as a result, the support rollers are automatically set under their own weight so that each rests on its entire breadth on the appertaining track.
In this known construction the second axis extends in the direction of movement and is spaced above the appertaining support roller. As more detailed tests show, this results in a statically unstable system when forces occur which act laterally on the telescopic cover. If as a result of a transverse load on the telescopic cover the second axis which extends in the direction of movement shifts to one side or the other out of the vertical central plane which passes through the centre of the roller, then the vertical load results in a tilting moment which attempts to tilt the support roller about a horizontal axis passing through the centre of the roller, and thus leads to loading of the edges of the support roller which is most unfavorable from the point of view of wear.